声学声子库场影响下的半导体量子点-微腔系统控制单光子输运的理论研究

Quantum manipulation for single-photon transport in one-dimensional waveguide is one of the key problems in quantum computation and quantum information processing. At present, most works are based on the atom-cavity system to control the single-photon transport in one-dimensional waveguide. However, there are many difficulties using the atom-cavity system, such as the cooling、trapping and manipulation of the atoms, the cascading of the multiple atom-cavity systems, and the extendible quantum information processing. By contrast, the semiconductor quantum dot-microcavity system has many advantages, such as small size, easy integration, easy extension, and easy manipulation. Therefore, controlling single-photon transport in one-dimensional waveguide with semiconductor quantum dot-microcavity system can greatly reduce the difficulties of the experiment technique in practical application. However, the behavior of the semiconductor quantum dot-microcavity system is closely related to the acoustic-phonon reservoir. So in this project, we want to study the single-photon transport in one-dimensional waveguide controlled by semiconductor quantum dot-microcavity system. We adopt the master equation method to analyze the influence of the Markov and the short-time non-Markov effects of the acoustic-phonon reservoir, studying the effects of the pure dephasing and the cavity feeding on the single-photon transport for different values of the phonon- reservoir temperature, the quantum dot-cavity detuning and other controllable parameters. Based on the study, we can seek the best condition to control the acoustic- phonon reservoir. Our study will provide theoretical guidance for effective controlling the single-photon transport in one dimensional waveguide with semiconductor quantum dot-microcavity system.

一维波导中单光子输运的量子操控是量子计算、量子信息处理等领域的关键问题之一。目前大多数的研究工作是利用原子-腔系统控制一维波导中的单光子输运。对于原子-腔系统，原子的冷却、囚禁、操控、多个系统的级联以及可扩展的量子信息处理都存在着一定的困难。而半导体量子点-微腔系统具有体积小、易集成、可扩容、易操控的优势，可极大地降低实际应用中对实验技术的要求。由于半导体量子点-微腔系统的性质与声学声子库场密切相关，所以本项目中我们基于半导体量子点-微腔系统控制一维波导中的单光子输运，采用主方程方法研究声学声子库场的马尔可夫和短时非马尔可夫效应的影响，分析在不同库场温度和量子点-腔失谐等可控参数条件下，纯退相过程和腔场的增强作用对单光子输运的调控作用，从而寻找控制库场作用的最佳条件。研究结果将为利用半导体量子点-微腔系统有效地控制一维波导中的单光子输运提供可靠的理论依据。

一维波导中单光子输运的量子操控是量子计算、量子信息处理等领域的关键问题之一。本课题采用多种方法探索微腔-波导系统中单光子输运的调控机制，从而实现高保真量子信息处理，初步获得一些有意义的结果。首先，我们研究了在声学声子库场作用下，量子点-微腔与一维波导耦合系统中的单光子输运。研究发现，腔场的增强作用使得声子可以提供能量，形成量子点和空腔的有效非共振耦合。当量子点与腔场处于强耦合时，单光子透射谱线会出现拉比劈裂现象；其次，我们研究了利用原子与光力学微腔的耦合系统来控制一维波导中的单光子输运。研究表明，单光子的透射几率受光力学耦合强度、原子-腔失谐等参数的影响。在一定条件下,单光子输运谱线出现了类拉比劈裂现象或者多个双电磁感应透明窗口；另外，我们还研究了利用偶极耦合的微波谐振腔来控制波导中的单光子输运。研究表明，偶极微腔系统中的偶极干涉效应在光子的透射光谱中起着关键作用，我们讨论了微腔的Purcell因子、入射光子频率等参数的影响，以及光子输运过程中的混合透明效应和纠缠效应。该方案对实验噪声和缺陷也不敏感，故可以在劣腔系统中实现。本项目的研究内容将为基于微腔-波导耦合系统的单光子输运及量子信息处理提供一定的理论指导。项目资助发表SCI论文5篇，待发表2篇，培养硕士生2名。